In some fabrication processes, a hard mask is used to improve etching selectivity relative to dielectric material. However, the hard mask (e.g., a metal hard mask) can shrink on the edges (i.e., hard mask pullback) after dry etching and wet cleaning processes. During a seed metal layer deposition afterwards, the hard mask pullback may cause undesirable overhang on the structure that reduces opening of the trench formed below, which interferes with metal filling.